Machine for decorticating maize cobs



July 17, 1934. E. E. c. SERRE MACHINE FOR DECORTICATING MAIZE COBS Filed Dec. 2, 1930 2 Sheets-Sheet 1 July 17, 1934. E. E. c. SERRE MACHINE FOR DECORTICATING MAIZE C055 2 Sheets-Sheet 2 Filed Dec. 2, 1930 znwnfar V v/yzp Patented July 17, 1934 STATE-S MACHINE FOR DECORTICATING MAIZE COBS 1 Eugene Edmond Charles Serre, Paris, France Application DecemberZ, 1930, Serial No- 499,568

In France December 2, 1929 4 Claims.

The present invention relates to improvements in machines for decortioating maize cobs, of the' in each group, and of such section that the distance between the two most contiguous generating lines ranges through a series of maxima and minima, the more remote generating lines serve ing to seize the leaves, and the more adjacent generating lines to seize them and detach them from the cob. To facilitate gripping of the leaves, the remote generating lines, especially in front of the active edges, that is to say those preceding, in the direction of rotation, the generating lines r of wide radius, are partially or completely furnished with fine needles constituted, for example,

by shark skin. V A

According to one improvement of the invention metal points, mounted singly at intervals on the generating lines situated in front of the active edges, constitute said needles.

According to a preferred embodiment, each point is in the form of a triangular pyramid, the 7 base of which is approximately at right angles to the edge situated in the right section of the cylinder and in front in the direction of rotation of the cylinder. 7

According to another improvement, in the case of several groups of juxtaposed and inclined roll- 0 ers, one of the rollers of each group turning in movable bearings, the rollers of one group are oifset by 90, in their direction of rotation, in relation to the adjoining group in such a way that, when one of said groups is in the operative position (members of maximum radius coinciding) the adjoining group is in the neutral position (mem bers of minimum radius coinciding), the result being to give the cylinder which is operating the necessary room for its momentary divergence.

Other improvements will become apparent from the following description.

In the accompanying drawings, which are given solely by way of example, Fig. 1 is a vertical longitudinal section, along the line 11 of Fig. 2, of an improved machine according to the invention.

Fig. 2 is a corresponding plan.

Fig. 3 is an end elevation.

Fig. 4 is a diagrammatic sectionalong the lin 4-- i of Fig. l.

Fig. 5 is a cross section on a larger scale, of two groups of cylinders.

Fig. 6 is a perspective View of a point.

Fig. 7 is a view of said point fromabove.

Fig. 8 is a perspective view" of another point, of which Fig. 9 is a View from above. I

Fig. 10 is a vertical section of the stop-motion device with which the machine is preferably equippedL a Fig. 11 is a horizontal section along the line l111 of Fig. 10. I

The various improvements forming the object of the invention have been combined in the embodiment shown in Figs. 1-3, but it will be understood that they may be employed separately, or in any combination whatever.

According to the embodiment shown, the ma chine is composed of a frame consisting of two iron longitudin'als 1 andla, which are parallel and oblique, and are connected together by two cross-frame members 2 and 2a, supported on the legs 3. On these cross-frame members are mounted several groups of paired rollers or cylin ders, 4, 5, 4a, 5a., 4b, 5b, which will be described later.- Any number of pairs of cylinders may be employed. One of the cylinders in each group (such as 5a, 4a, 5b) is mounted in fixed bearings, whilst the other cylinders are mountedat one or both ends, in movable bearings, supported by levers 6, 6a., 619 (Fig. 3) oscillating on axes '7 7a, 7b. Springs 8, 841,822 tend to bring the movable roller towards the fixed roller of the same group. According to the invention, these springs are fixed on a crossbar 9, the vertical level of which can be adjusted by means of strainers 10 and 10a, which thus enable the effort required to separate the two rollers of the same group to be regulated at will. I

According to the invention, the preferred cross sectional form of the rollers is that shown in Fig. 5. It is constituted by four straight lines 11, 1'2 ll', l2, each-pair enclosing a highly obtuse angle, and being connected together by twocircular arcs 13 and 13". The rollers of one and the same group are approximately tangential-whentheir circular portions are face to face (rollers 4 and 5, Figs. 4 and 5), and on the contrary, leave an intermediate gap when the flat faces are opposite each other (rollers la and 5a). The intersection of the fiat faces 11 and 12' with the cylindrical portions 13 and 13' constitutes the working edges 14 andle', the directions of rotation of the rollers being those indicated by the arrows (Fig. 5).

According to one characteristic of the present invention, the shark skin or metal fabric which usually covers intermittent portions of the work-' ingedges of the rollers, is replaced by points I6, 16 mounted singly, at intervals, in front of and near the working edges 14, 14' of the rollers.

These points are preferably constructed (Figs 6 and 7)" of a tempered steel stem 17, provided with a widened shoulder 18 and terminating at the" extremity in a'sh'arp point 19. The stem l'l of these points may be split, at 20, part of the way along," in' order to facilitate insertion by force into one of the holes 21 provided for that purpose at intervals in the rollers, thusfa'cilitat-r ing insertion and replacement.

These points may be of several forms, the most rational being, in any event, that of a triangular pyramid (Figs. 6 and '7), on a plane 18 at approximately right angles to the edge 22 situated in a right section of the roller, facing the direction of rotation.

The advantage of such a shape is manifest. Even when blunted, the point still possesses maximum penetrating power, and therefore an assured grip, even when worn. Moreover, since the edge at right angles to the base of the point is situated in the plane of 'rotation of the rollers, it follows that this edge alone comesin contact with the grains on the cob when this latter begins to be partially deprived of its leaves, thereby enabling said leaves to slide easily over said edge and the point to disengage itself between the interstices of the grains, a circumstance which prevents that crushing of a large number of grains which is inevitable with any other shape or system.

Moreover, since the sharp edge of the point forms a right-or rather slightly obtuse-angle with the flat surface of the roller, there is no danger of the leaves hanging thereon, the part played by these points being solely to grip the leaves sufficiently to bring them to be seized between the convex portions 13 and 13' of the rollers, which, in turning, tangentially grip them, and assure the straightening out of the cobs on their base and'the detachment of the leaves on their stem.. Apart from the advantages already mentioned, this idea does away with the employment of the usual brushes, located below the rollers and frequently tangling the leaves and thus leading to frequent stoppage of the machine.

Figs. 8 and 9 represent another form of point, which is similar and more easily made, the point being composed of a portion of a cone, mounted or not on its base under the same conditions as the point in Figs. 6 and '7.

It is evident that, in order to function properly, the points 16, 16' must be mounted so as to face one another on each pair of rollers, otherwise their action would be less effective. Moreover, they should be disposed as near the working edges l4, 14 as possible, but in such a way that their apex is always well inside the circumference of the rollers, since otherwise, in work, ing, they might knock against each other or against the opposite rollers.

The acute angles forming the working edges of the rollers being abated by two wide chamfers 11 and 12', which are provided with the bores 21 for housng the points, the biting actionof the rollers on the small cobs is thus diminished, so that, when these are seized by the point, they are not broken between the rollers, an occurrence which would not fail to cause a good number of the grains to be detached.

According to another characteristic of the invention narrow grooves 23 (Fig. 5) are provided at intervals along the generating line of the circular portions 13' 13 of the rollers, the arrangement being such that the grooves on one cylinder are'offset in relation to those on the opposite cylinder, that is to say, they never come face to face as the cylinders revolve.

The object of these grooves is to assure a more energetic detachment and removal of the leaves, especially when, after the machine has been in operationfor a certain time, this portion of the rollers has become polished, and even glazed, by the friction of the dry leaves, the leaves being, in

consequence, caused to slip between the rollers and become difficult to strip off the base of the cob, mainly when this is seized by the point.

According to another improvement the various cylinderswhen the machine comprises several groupsare driven by the same train of gear 24, mounted on the end of the cylinders and concealed under a chute 25 through which the stripped cobs are discharged. This drive is rendered possible by the special sectional shape of the cylinders and a special method of regulating the actuating gear. The gear pinions are keyed'in such a way that there is an offset of 90 in the angle of rotation between each group of cylinders (Figs. 3, 4 and 5). In this manner, when one group of cylinders is in the operative position (circular portions 13, 13', of maximum radius, face to face), the adjoining group is in a neutral position (portions of minimum radius face to face) and vice versa. Owing to this arrangement the cylinder in operation and mounted on the movable bearings has ample space for moving away when a bunch of leaves, or the stems of the cobs, pass through the group of cylinders which are in work.

The arrangement of this group of cylinders, mounted side by side in the same plane, offers a considerable advantage since it allows the cobs to be fed into the machine in bulk and in disorder. Since the neighbouring cylinders of each group turn in opposite directions, and each in an opposite direction in relation to their external tangential plane, it follows that the cobs which fall on to them, or between the two, are at once thrown off on to one group or the other.

Moreover, this division balances the work and eases the running of the machine, so that for this reason less power is needed for driving.

In order to straighten out and facilitate the movement of the cobs in the direction of their major axis, and thus prevent some of them from rolling crosswise over the rollers, the machine may advantageously be provided (when it comprises several groups of juxtaposed rollers) with a so-called separator disposed above and between each group of rollers, and extending over a fairly large portion of their length, so as to partition off each group.

Each member of the separator consists, for example (Figs. 1-4) of a strip of thin sheet metal 26, 26a, terminating in an elongated point 27 towards the top of the rollers and rigidly mounted, so that its plane is always situated in the median plane separating each group of rollers. The separator comprises as many members, less one, as there are groups of rollers. These members 26, 26a are connected together by a crossbar 28, which is attached to the cheek plates 29 and 29a forming the chute.

The separator is mounted along the cylinders in such a way that the ends of its members are at a certain distance from the upper extremity of the rollers, that is to say, behind the feed zone of the rollers.

Owing to this precaution when, in feeding the machine, a thick layer of cobs is thrown anyhow over the top of the rollers, the said cobs are able to distribute themselves automatically above each group, without jamming, under the frictional action of the rollers alone.

Of course, the feed to the upper part of the rollers may be effected in any way whatsoever. There is always an advantage in arranging it in accordance with the invention, in the manner represented in Figs. l-3, as a chute or hopper 30,

l-lO

framed by the two cheek plates 29 and 29a, forming a chute and diverging upwards. The opening of this chute is provided with a closure, which is adjustable vertically above the plane of the rollers, in accordance with the average thickness of the cobs. This closure consists of a strip of sheet iron 31 mounted in the two extreme edges 32 and 32a of the chute, by means of two thumbscrews 33 and 33a, or two slides which enable the opening above the plane of the rollers to be adjusted.

Instead of sliding, the closure plate may be hinged, towards the outside of the chute, on an axis integral with the extreme edges of the chute. In such case, however, its weight should be such that it will regularize and limit the issue of the cobs escaping from the chute, by opening to a greater or smaller extent under the sole influence of their thrust.

The prime importance of an adjustable opening will be recognized. It has already been seen that the juxtaposition of the groups of rollers on one and the same plane (owing tothe special ofisetting of said rollers) enables the machine to be fed with successive layers of cobs emptied in in bulk. Owing to the feed chute and its special closure means, it can be filled with several layers at a time, eitherif the size of the machine permitsby the basketful or sackful, thus rendering the feeding of the apparatus self-automatic. In fact, only that layer of cobs which is in contact with the rollers can pass through the opening in the chute. The weight of the overlying layers exerts a certain pressure on these cobs, which are far more rapidly stripped of the bulk of their leaves. They are drawn out of the chute by the rotation and slope of the rollers, and in this manner an automatic distribution of the cobs is obtained, without any mechanical device, in that the cobs in the upper layers replace those that have been drawn out, and so on.

Preferably, as is shown in Figs. 1 and 2, a chute 34, of the same width as the frame, and terminating in a mouth, is secured at the back end of the machine by two axes or bolts 35, on which it is adapted to turn, thus enabling its height to be adjusted in accordance with that of the receptacle intended to collect the stripped cobs.

The provision of this chute for the removal of the cobs checks the abrupt descent of these latter into the receptacle, under which conditions many of the grains would be detached by the impact, and it also enables said receptacle to be placed as far from the machine as possible, in order to prevent the leaves accumulating under the frame from falling or being pushed into said receptacle.

The machine may also be provided with a device intended for separately recovering the small quantity of grains which may have been detached from the cobs and have fallen with the leaves. In such case there is disposed below the rollers a steeply pitched grating, adapted to reciprocate transversely in order to facilitate the removal of the leaves, the grains being collected in a receptacle of any kind, placed on the ground below the grating. This reciprocating grating may be replaced by an endless screen, driven by the rollers or the main shaft, and discharging the leaves on one side of the machine.

According to another improvement of the invention, the flywheel pulley 36 which drives the main shaft 37 is provided with a stop-motion, which automatically stops the machine in the event of any abnormal resistance being encountered. This device prevents the breaking of some member when a heavy body (stone, piece of wood, etc.) present among the cobs, becomes jammed between the rollers. Said device may be of the friction-clutch, or any other, type.

One embodiment is shown by way of example in Fig. 10. According to this example the pulley 36 is mounted idly on the main shaft 37, and is provided round its bore with one or more deep V-shaped recesses 38, in which the teeth 40 of a sleeve 41 engage under the pressure of a spring 39. This sleeve 41 is keyed so as to slide on the shaft 3'7. A set screw 42 compresses the spring 39 against the sleeve 41, so as to enable the sensitiveness of the stop-motion device to be adjusted at will.

The nose of the sleeve 41 is provided with a groove 43, which accommodates a pawl 45 pivotally mounted on the sleeve by means of a fixed pin 45. This pawl is kept in contact with the main shaft 37, by means of a spring 46 attached to the sleeve. A notch 47 is provided in the said shaft on the line of contact with the pawl 44.

Under the effect of an unusual resistance occurring in any part of the machinewhich influence is manifested by slowing down the shaft 37the driving pulley 36, in continuing to turn, forces the sleeve 41 outwards, against the thrust of the spring 39, until the teeth 40 on the sleeve issue from the notches 38 in the pulley 36. At that moment the end of the pawl 44 is caused by the spring 46 to engage in the small notch or groove 47 provided in the main shaft 37, whereupon the pulley becomes idle and the machine stops.

A loose pulley 48, one edge of which fits loosely in the flange of the flywheel, may be mounted idly on the outer portion of the sleeve.

The invention is, of course, not restricted to the embodiments shown and described, which are given solely by way of example.

What I claim is:--

1. In a decorticating machine, a pair of decortieating rollers, each formed with two diametrically opposite segmental surfaces, and intervening flattened surfaces, meeting the segmental surfaces at angles forming working edges, said rollers be ing armed with metal points constituting needles for gripping leaves, and located forward of said working edges relatively to the direction of rotation of said rollers, the latter being arranged and adapted to rotate in approximate contact at their segmental surfaces, and said points, having their gripping edges wholly within the circumference line of the segmental surfaces.

2. A decorticating roller as claimed in claim 1, in which the metal points are of substantially pyramidal shape and disposed with their axes inclined in the direction of rotation of the rollers.

3. A decorticating roller as claimed in claim 1, in which the two segmental surfaces, are connected by two intervening straight portions, each composed of two plane surfaces defining an obtuse angle.

4. A pair of rollers according to claim I, having each narrow concave grooves offset in relation to those on the opposite roller, provided at intervals on the generating lines of the circular portions of the rollers.

EUGENE EDMOND CHARLES SERRE. 

